How Data is Collected

River level data is collected at gauging stations using a variety of electronic sensors that measure the level of the water. In the majority of cases level is measured using a shaft encoder driven by a float and counterweight arrangement. Pressure sensors that translate water pressure into level are also used. Rapid fluctuations in water level due to surface waves are damped by placing the level sensor in a stilling well.

Information from the sensor is stored on a data logger, usually at 15 minute intervals. The data loggers are connected to the telephone network enabling SEPA to collect the data via a telemetry system. Most stations are automatically downloaded and the data archived once each day.

Once collected from the gauging stations the unverified data is exported automatically to the web site. Occasionally data for a site may be unavailable or incorrect. This is generally caused by a failure in the telephone network, an instrumentation fault or a failure in SEPA's computer systems. Problems will generally be resolved within a period of a single day up to a week depending on the nature of the problem.

The website updates 6 times during the day to allow for failed transmissions - data may therefore be briefly unavailable during these times.






Whilst every effort has been made to ensure the accuracy of the information provided, neither Scottish Environment Protection Agency, nor its employees or agents can be held responsible for any inaccuracies or omissions, whether caused by negligence or otherwise.